Roll-changing apparatus for a rolling mill



April 8, 1969 T. KARNKOWSKI ROLL-CHANGING APPARATUS FOR A ROLLING MILL Sheet H of 3 Filed Feb. 21, 1967 INVENTOR. 7105052 flkA/KOWS/K/ BY jMM 52 4 W Sheet 2 of s INVENTOR.

April 8, 1969 T. KARNKOWSKI ROLL-CHANGING APPARATUS FOR A ROLLING MILL Filed Feb. 21, 1967 April 8, 1969 T. KARNKOWSKI ROLL-CHANGING APPARATUS FOR A ROLLING MILL Sheet Filed Feb. 21, 196'? mW M M W w Q U M w w 3,436,945 ROLL-CHANGING APPARATU FQR A ROLLING MILL Tadeusz Karnkowski, New Haven, Conn, assignor to Textron, Inc., Providence, KL, a corporation of Rhode Island Filed Feb. 21, 1967, Ser. No. 617,545 Int. Cl. 321!) 31/08 US. Cl. 72239 14 Claims ABSTRACT OF THE DISCLOSURE This invention relates to apparatus for changing rolls in a rolling mill, and relates more particularly to a rolling mill for rolling steel, for example, having as a part thereof means for quickly and efficiently changing the rolls when they become worn or their work surfaces are otherwise adversely affected, without interruption of the passage of material in the so-called pass line of the roll ing mill or without first removing the material from the pass line, for changing one or more rolls of the mill. The aforementioned rolling operation may employ a plurality of such rolling mills arranged in tandem or may employ a single rolling mill and, while not limited thereto, is well suited for employment in a rolling mill having only two Work rolls in superposed relation to one another.

In the rolling of strip steel, for example, for the purpose of reducing the thickness of the material, it has been found necessary by some to change the rolls of a mill for dressing of the work surfaces thereof at short intervals of operational time. Hence it is important in such a mill op eration to reduce to the minimum the down time for changing rolls.

It is believed that heretofore it has been necessary in changing rolls of a mill to either remove the material from the pass line between cooperating rolls before changing the rolls of the mill or to cock or pivot one of the rolls about an axis to provide clearance of the thus cantilevered roll, and the chock on the distal end thereof, with t reference to the strip of material in the pass line, for removal and replacement of at least one of the rolls of the mill.

This is not necessary in accordance with the present invention and, in fact, if desired in the particular processing operation, the passage of material may be continued during roll changing which makes the rolling mill highly suitable for a continuous process such as a galvanizing process, for example, in which the strip of mate rial may be tempered by the mill prior to entering a galvanizing station in an uninterrupted manner. The present invention contemplates apparatus for the bodily movement substantially in parallelism of one work roll with reference to its companion in a manner to separate therefrom or, to state it another way, away from the pass line, without intentionally pivoting the roll, and contemplates means for supporting the aforementioned rolls in these relatively separated positions, providing clearance between the roll and one of its chocks with the strip of material in the pass line, and means for moving, while in substantially parallel relation to one another, the rolls out of the mill for roll-changing purposes.

3,436,945 Patented Apr. 8, 1969 One object of the invention is to provide an improved rolling mill well suited for rolling metallic material such as steel, for example. Another object is to provide a rolling mil in which rolls of the mill may be changed very quickly and efficiently, which is well suited to a Z-High stand of rolls but not limited thereto.

A further object of the invention is to provide such roll-changing means which does not require the cocking or pivoting of one roll with respect to the roll with which it cooperates, for roll-changing purposes which permit new rolls or reground rolls, that is, rolls which had become worn or affected in other ways by the material worked upon and then were resurfaced or dressed, to be inserted into the mill stand as replacements from the operators side thereof and be ejected from the same side of the mill, in which the rolls may be driven while in mill operation from the other side of the mill.

Another object of the invention is, for roll-changing purposes, to provide in such a mill having means to relatively separate cooperating work rolls, means to provide clearance between cooperating ones of the respective pairs of roll chocks, and including a trolley or carrier movable toward the operators side of the mill by which one roll in its separated condition may be supported with additional support means, for substantially axial movement in a manner to eject the roll from the mill. Further objects will be apparent to those versed in the art from the following detailed description of the presently preferred form of the invention embodied in a rolling mill.

In the drawings:

FIG. 1 is a fragmentary, broken, elevational view partially in section illustrating a rolling mill embodying the invention, showing two cooperating work rolls separated relatively to one another for roll-changing purposes;

FIG. 2 is an elevational view showing the left side of the mill rolls, as viewed in FIG. 1;

FIG. 3 is a view similar to FIG. 1 illustrating the rolls of the mill in different axial positions during roll chang- FIG. 4 is a view similar to FIG. 1 but showing the work rolls of the mill in their operative positions;

FIG. 5 is an enlarged sectional view taken on line 5-5 of FIG. 3; and

FIG. 6 is an enlarged, fragmentary, elevational view similar to FIG. 1 further illustrating the aforementioned roll trolley or carrier and its associated mechanism.

In the drawings the rolling mill is indicated generally at 10 and is shown in association with a mill floor 11. The rolling mill comprises upright windowed frame parts 12 and I3 laterally spaced apart having their Windows in alignment with one another, the frame parts being supported on a suitable bed including a common support 14 which may be recessed in the floor as shown. The upper part of the rolling mill, not shown, includes means interconnecting the frame parts. The illustrated rolling mill is of the 2-High type having cooperating work rolls 15 and 16 shown (FIG. 4) received within the mill with the necks thereof received in the respective Windows of the frame parts 12 and 13. The work or the strip of material in the pass line of the mill extends between the rolls 15 and 16 during operation of the mill, as shown in FIG. 4.

The roll 15 of the mill is the upper or loading roll which resists upward pressure from the work and which carries on its necks bearing chocks 15 and 15 respectively, vertically slidable in the Windows of the frame parts 12 and 13. The illustrated work surface of the roll 15 cooperates with a similar surface of the roll 16 by virtue of the weight of the former, or the last-mentioned roll may be loaded by conventional loading devices. The roll 16 is a lower or bearing roll having similar roll necks disposed in similar manner receiving similar bearing chocks 16 and 16* received in the respective windows of the frame 3 parts 12 and 13, from which the chocks 15 and 15 are supported.

The roll necks 15 and 16 of the rolls 15 and 16, respectively, at the right-hand side of the mill stand, as viewed in FIG. 4, are driven by conventional means, including detachable coupling elements 17 and 18 respectively, each of which may be keyed to the companion roll neck for driving purposes. Conventional carrier elements 17 and 18 are illustrated in association with the respective coupling elements 17 and 18.

The roll 16 is supported through its bearing chocks on a sled 19 received in the windowed frame parts 12 and 13, and there is provided a supporting guideway 20 on which the sled (FIG. 3), equipped with wheels 21 is movable in a direction axially of the rolls. The guideway 20 extends beyond the mill stand at the operators side thereof, as best shown in FIG. 3. In the last-mentioned view the sled is shown in full lines retracted from the windowed frame parts 12 and 13 of the mill, with the rolls 15 and 16 thereon, and shown in phantom in the position which it assumes when the rolls 15 and 16 thereon are received within the frame parts 12 and 13.

In the form shown by way of example, the sled is moved by the piston rod 22 of a fluid cylinder, not shown, having a threaded end extended through a plate 23 suspended in fixed relation from the sled 19, as shown. The piston rod is axially fixed with reference to the plate 23 by means including nuts 24 (FIG. 3) threaded on the aforementioned end of the piston rod. The arrangement is such that extension of the piston rod 22 serves to extend the sled 19 with the work rolls thereon into the aforementioned frame parts of the mill stand while retraction of the piston rod 22 serves to move the sled 19 in the opposite direction or to the position shown in FIG. 3 in full lines.

When the rolls 15 and 16 are in their retracted positions shown in full lines in FIG. 3, the roll 16 remains sup ported from the sled 19 while one end of the roll 15 is supported through its chock 15 by a pair of spaced blocks 25 interposed between the bearing chocks 15 and 16 Each block 25 has a pin 26 extending therethrough received in an appropriate blind hole in each of the lastmentioned chocks. The blocks 25 serve to maintain the last-mentioned end of the roll 15 with its chock in upwardly spaced relation to the roll 16, that is, with reference to the position of the roll 15 shown in FIG. 3. The pins 26 of the blocks tend to prevent any axial or angular dislocation of the roll 15 with respect to the roll 16-.

In this position of the roll 15, the other end thereof is suspended from the mill stand through the aforementioned trolley or carrier, to be described in detail hereinafter, through the chock 15 and it will be noted that, as shown in the last-mentioned view, the chock 15 is suspended in such a manner as to provide clearance for the work in the pass line of the mill as will appear more fully hereinafter.

When the rolls are operative in the mill stand, the aforementioned loading devices for the upper roll 16 cooperate with the chocks 15 and 15 to exert a downward pressure thereon. For this purpose the loading devices may comprise a pair of screw or hold-down elements, only one being shown and indicated at 28 cooperating with a raised portion 27 of the chock 15, as shown in FIG. 4. It will be understood from the foregoing that the hold-down or loading devices may be raised an appropriate distance to permit the roll 15 and the chocks associated therewith to assume the positions shown in phantom in FIG. 3. In this view the raised position of the roll 15' is exaggerated as is the raised position of the element 28 for the sake of a clear understanding of the movements of certain elements of the apparatus.

As best shown in FIG. 2, the chock 15 of the roll 15 is provided with two laterally spaced pairs of ears 29 and two pins 30, one pin 30 being received in each pair of ears 29. Two hook latches 31 are provided, one pivoted on each pin 30 to swing in a vertical plane and for cooperation with one of a pair of pins 32 constituting parts of a supporting trolley or conveyor mechanism previously referred to as a carrier which will be described in detail hereinafter.

As shown in this view, this trolley, a duplex mechanism, indicated generally at 36, comprises twin units, each comprising a pair of check plates 33, the plates of each pair being laterally spaced apart and receiving therebetween one of the aforementioned pins 32 with Which one of the hooks 31 cooperates. The check plates of each pair are supported (FlG. 5) in turn by a pair of antifriction rollers 34 supported from the cheek plates by stub shafts 35.

The rollers 34 of each unit may be tapered as shown and be supported for rolling contact along one of a pair of I beams 37 suitably supported from the upper portion of the mill stand, as indicated in FIG. 1, so that each trolley unit is movable freely lengthwise of the one of the I beams or axially of the rolls in the positions which the rolls assume when within the windowed frame parts 12 and 13 of the mill stand. The I beams 37, only one of which is shown in FIG. 3, extend beyond the windowed frame part 12 or, to state it another way, extend beyond the mill stand toward the operator. As shown in the lastmentioned view, a support 37 is provided for the projecting end of the I beam 37.

In the illustrated form of the invention there is provided for operation of the latch books 31 a pair of fluid cylinders (only one shown at 39), one for each hook, for hooking or latching each element 31 and for unhooking or unlatching the element 31. It will be understood that these cylinders may be provided for power operation of the latch elements 31 but, if desired, the latch elements may be operated manually. The construction, arrangement and operation of the fluid cylinders which work in unison are identical and, therefore, only the one shown in FIG. 1, for example, need be described. As shown in this view, one end of the cylinder is pivoted to a stationary support on the chock 15 and has at the other end thereof an extensible and retractable piston rod 40.

The distal end of the piston rod 40 is pivoted to the hook or latch member 31 intermediate the ends thereof, as indicated in FIG. 1. Also as shown in this view, the latch element 31 is in hooked or engaged condition or in a position in which it may support by suspension therefrom the chock 15 and the righthand end portion of the roll 15, as viewed in FIG. 1. The hook or latch member 31 is rendered inoperative or unlatched by raising movement of the hook 15 a distance sufficient to free the latch member 31 of the load of the chock 15 and permit clearance of the latch element 31 with respect to the pin or keeper 32 so that on retraction of the piston rod 46, the hook or latch element 31 swings free and clear of the trolley unit including the elements 32- 35. It will be understood, as previously indicated, that the latches 31 of the aforementioned pair act in unison through the operation of the fluid cylinders. The fluid connections of the cylinder 39 illustrated in FIG. 1 are not shown, but it will be understood that they may be conventional for the purpose of extending the piston rod 40 and retracting it. It will be understood that in order for the latches 31 to swing to their latched positions from their unlatched positions, the chock 15 must be raised from the position of FIG. 4, the unlatched position of one of the elements 31 being shown in FIG. 4.

In rolling mills of the type such as shown and described, it is conventional to employ so-called rollbalancing means intermediate an upper and a lower roll to impart an upward thrust on the upper roll during operation of the mill. The thrust may be sufiicient to raise the upper roll with reference to the lower roll when any hold-down pressure is relieved. The term balancing as used in the industry has a technical meaning and does not mean balancing in the broad sense of the word inasmuch as the operation of this balancing means during the operation of the mill is not suflicient to counteract both the weight of the upper roll and the downward pressure exerted on the upper roll by hold-down devices such as previously described herein.

The present invention contemplates the use of this conventional balancing means or an adaptation thereof for a purpose in addition to that of balancing, namely, lifting the upper roll with reference to the work and the lower roll to facilitate roll changing as will be detailed hereinafter. It is understood by those versed in the art that the degree of relative separation of the upper and lower rolls for roll-changing purposes may be relatively small but is shown in the drawings exaggeratedly for the purpose of a clear understanding of the inevntion.

In the illustrated form the so-called balancing means includes fluid cavities 42 in the respective chocks of the lower work roll 16 which, as indicated in FIG. 1, face upwardly to receive fluid-operated ramlike elements 43, a pair of the fluid cavities receiving a pair of rams provided in each one of the pair of chocks 16 16 The disconnectable fluid connections for the fluid cavities 42, not shown, may be of a conventional type.

The working condition of the rolls of the mill is shown in FIG. 4 wherein the work or the strip of material passing between the cooperating rolls is indicated at 45 in the pass line of the mill. There is illustrated in this view a load exerted on the roll by the hold-down devices including the aforementioned element 28. As further indicated in this view, the aforementioned balancing means is in operative condition, with the rams 43 engaging the under sides of the respective chocks 15 and 15 of the upper roll 15. The rolls of the mill are driven in a conventional manner through the respective coupling elements 17 and 18.

When it is desired to replace at least one of the work rolls shown in FIG. 4, the hold-down devices, including the element 28, are operated to relieve downward pressure on the roll chocks of the roll 15 or, to state it another way, retract it a distance suflicient to permit the rolls to separate relatively to one another a distance sufiicient to clear the work or move from the relative positions of the roll shown in FIG. 4 to that shown in phantom in FIG. 3. At this time the mill is rendered inoperative but it will be understood from the foregoing that the work 45 may continue to pass intermediate of the rolls 15 and 16. When downward pressure on the work 45 is relieved in this manner, the work tends to free itself of the lower roll 16, as indicated in FIG. 11, and assume the position shown somewhat exaggeratedly (for the sake of clarity of the disclosure) in the last-mentioned view.

It will be understood from the foregoing that when the pressure of the hold-down devices is relieved as aforesaid, the rams 43 exerting an upward thrust on the chocks of the upper roll may through the then pressure in the fluid cavities 42 raise the roll 15 by its chocks. If the fluid pressure is not suflicient for this purpose, it will be evident that additional fluid pressure may be applied by a conventional means through the cavities to the respective rams to raise the roll 15 with its chocks to the desired position.

The carriers 17 and 18 associated with the coupling elements 17 and 18 respectively serve as weight supports for the roll-driving mechanism, and when the roll 15 is raised in the aforesaid manner, the carrier 17 is raised accordingly with the coupling element 17 remaining connected to the roll neck 15. Conventional driving mechanisms for the rolls of a mill include appropriate means for permitting this separation of the rolls.

The hooks or latch elements 31 on the chock 15 of the upper roll are operated in unison as aforesaid, each by one fluid cylinder 39, to move the latch elements 31 from the unlatched or angular positions to substantially vertical positions, indicated in phantom in FIG. 6. It will be appreciated that during this movement of the latch elements the aforementioned latch-operating fluid cylinders pivot on their supporting axes.

When the rolls are separated as aforesaid, the blocks 25, previously described, each having a pin 26 extending therethrough, may be manually inserted intermediate the chocks 15 and 16 and indexed as aforesaid with reference thereto. Then the rolls may be moved relatively toward one another. The roll 15 with its associated chocks may be lowered so that the chock 15 and, therefore, one end portion of the roll 15 may be supported from the blocks 25 from the chock 16 to prevent axial or angular shifting of one chock with reference to the other, while the latch elements 31 engage the respective latch pins so that the chock 15 may be suspended, supporting the other end portion of the roll 15 from the conveyor mechanism 36 previously described.

The roll 15 may be lowered as aforesaid, without reengaging the work 45, by retraction of the rams 43 which, of course, may be permitted by letting fluid escape in a conventional manner from the respective fluid cavities 42. To clear the work the rams 43 are retracted. The fluid connections to the cavities 42 may thereafter be disconnected from the respective chocks 16 and 16 to permit removal of these chocks from the broken-line position of FIG. 3 to the full-line position thereof on the sled 19.

When the rolls 15 and 16 are supported in the lastmentioned manner, the fluid cylinder associated with the aforementioned piston rod 22 recessed in the floor 11 may be operated to retract the rod 22 and thereby move the rolls on the sled to the full-line position of FIG. 3 when and as the aforementioned coupling elements 17 and 18 of the roll-driving mechanism are disconnected from the roll necks 15 and 16 respectively. It will be appreciated that during this movement rolls 15 and 16 move in unison from the broken-line positions of FIG. 3 to the full-line positions thereof, with the right end portion of the roll 15 and its chock suspended from the trolley mechanism 36 so that the rolls may clear the work during their removal from the mill stand. It will be appreciated that during this movement each trolley unit, which is comprised of the elements 3235, moves along its companion I beam on the rollers 34 thereof from the position indicated in FIG. 4 to the position indicated in FIG. 3, in which the rolls are retracted from the mill stand in a position in which access may be had to the roll-s and their associated chocks for removal from the sled 19 as by a crane, all without disturbing the work in the pass line of the mill.

When the rolls are in the full-line positions shown in FIG. 3, a sling (not shown) from a crane may be looped around the upper roll and tightened to support this roll and its chocks in position. The sling may then be operated by the crane to raise the last-mentioned roll a distance suflicient for the hook or latch elements 31 to clear the respective pin or keeper elements 32 as by swinging movement in a clockwise direction, as viewed in FIG. 3, on operation of their associated fluid cylinders. To clear the roll and associated mechanisms from the mill stand the sling is thereafter lowered a short distance.

Thereafter the sling may be operated by a crane to remove first the upper roll and then the lower roll from association with the mill stand for replacement. It will be understood, of course, that subsequently, if it is found that only one of the rolls has a damaged work surface, the other may be replaced in the mill with a new companion.

It will be understood from the foregoing that, at least when viewed broadly, the roll-changing mechanism is not restricted to apparatus limited to the removal and replacement of a pair of mill rolls for the reason that the lower illustrated roll 16 does not per se play any role in a roll-changing operation. Only the chocks of the roll 16 or their equivalents play a part in this operation.

The operation of the apparatus to replace rolls in the mill will be apparent from the foregoing description of the operation of the apparatus to remove rolls therefrom and involves, as will be readily apparent, the previously described steps followed in reverse order.

While one form of the rolling mill has been illustrated in the drawings and described above, it will be apparent to those versed in the art that the invention may take other forms and is susceptible of various changes in details without departing from the principles of the invention and the scope of the appended claims. For example, it will be readily apparent that the roll-supporting and indexing means 25, 26 illustrated as comprising a pair of blocks, each having a pin extending therethrough, may take another form.

What is claimed is:

1. In roll-changing apparatus for a rolling mill having a windowed stand receiving therein a pair of cooperating work rolls including bearing chocks on the respective roll necks vertically movable in the stand, provided with support means to enable at least one of the work rolls to be moved into and out of the stand, the combination comprising means for vertical adjusting movement of said one of the rolls toward and away from its neighbor substantially in parallelism thereto, between which rolls there is provided a work pass line in the mill, a trolley supported on the mill stand for movement from the vicinity of one side of the stand across the stand to a position in which it may extend beyond the other side of the stand, axially of said one roll, having as a part thereof a latch element thereon for the support of one chock of said one roll when the latter is adjusted as aforesaid away from its neighbor, to clear together with the working face of the roll supported thereby the plane of the work, said adjusting means being operative to clear said chock when said latch ele ment is operative, and latch means on said one chock for cooperation with said latch element, operative when said one chock is in the last-mentioned position thereof, so that the work is cleared during removal of said one roll when supported on the first-mentioned support and said trolley.

2. Roll-changing apparatus as defined in claim 1 Wherein said support means comprises a power-operated sled shiftable to project into the windowed mill stand and out therefrom.

3. Roll-changing apparatus as defined in claim 1 Wherein said means for vertical adjusting movement of said one of the rolls comprises a jack mechanism supported from said support means.

4. Roll-changing apparatus as defined in claim 1 wherein said support means comprises a power-operated sled to project into the windowed mill stand and out therefrom, and wherein said means for vertical adjusting movement of said one of the rolls comprises a jack mechanism sup ported from the sled.

5. Roll-changing apparatus as defined in claim 1 wherein said trolley is of duplex character, each unit of which comprises two pairs of rollers supporting a pair of cheek plates laterally spaced apart and suspending therebetween a pin constituting said latch element, and wherein the rollers are movable along a guideway provided on the mill.

6. Roll-changing apparatus as defined in claim 1 wherein said latch element on the trolley and said latch means on said one of the chocks comprises a keeper pin on one of the members and a power-operated latching hook on the other of the members.

7. Roll-changing apparatus as defined in claim 1 wherein said latch element on the trolley comprises a fixed keeper pin and the latch means on said one of the chocks comprises a power-operated latching hook.

8. Roll-changing apparatus as defined in claim 1 wherein said rolls of the mill are driven and said roll has a slipout detachable connection from the driving mechanism.

9. Roll-changing apparatus as defined in claim 1 wherein said support means comprises a power-operated sled shiftable to project into the windowed mill stand and out therefrom, said means for vertical adjusting movement of said one of the rolls being interposed between the respective chocks of the rolls, the chocks of the other roll being supported on the sled so that the pair of rolls may be removed together.

10. Roll-changing apparatus as defined in claim 9 wherein said means for vertical adjusting movement of said one of the rolls comprises a jack mechanism, and wherein there is provided spacing means between the other chock of said one roll and the companion chock of the other roll, insertable for support purposes, before the jack mechanism is retracted to clear said chock as aforesaid.

11. Roll-changing apparatus as defined in claim 9 wherein said trolley is of duplex character, each unit of which comprises two pairs of rollers supporting a pair of check plates laterally spaced apart and suspending therebetween a pin constituting said latch element, and wherein the rollers are movable along a guideway provided on the mill.

12. Roll-changing apparatus as defined in claim 9 wherein said latch element on the trolley and said latch means on said one of the chocks comprises a keeper pin on one of the members and a power-operated latching hook on the other of the members.

13. Roll-changing apparatus as defined in claim 9 wherein said latch element on the trolley comprises a fixed keeper pin and the latch means on said one of the chocks comprises a power-operated latching hook.

14. Roll-changing apparatus as defined in claim 9 wherein said rolls of the mill are driven and said rolls have a slip-out detachable connection from the driving mechanism.

References Cited UNITED STATES PATENTS 3,221,530 12/1965 Swallow et al. 72-239 3,312,096 4/1967 Stubbs et al. 72238 RICHARD J. HERBST, Primary Examiner.

B. J. MUSTAIKIS, Assistant Examiner. 

